#define _CRT_SECURE_NO_WARNINGS 1
#include"Stack.h"

void StackInit(ST* ps)
{
	assert(ps);
	ps->a = (STDataType*)malloc(sizeof(STDataType) * 4);
	ps->top = 0;
	ps->capacity = 4;
}

void StackDestroy(ST* ps)
{
	assert(ps);
	assert(ps->a);
	free(ps->a);
	ps->a = NULL;
	ps->top = 0;
	ps->capacity = 0;
}

void StackCheck(ST* ps)
{
	assert(ps);
	assert(ps->a);
	if (ps->top == ps->capacity)
	{
		ST* tmp = (STDataType*)realloc(ps->a, sizeof(STDataType) * (ps->capacity * 2));
		if (tmp == NULL)
		{
			printf("realloc fail\n");
			exit(0);
		}
		else
		{
			ps->a = tmp;
			ps->capacity *= 2;
		}
	}
}

void StackPush(ST* ps, STDataType x)
{
	assert(ps);
	assert(ps->a);
	StackCheck(ps);
	ps->a[ps->top] = x;
	ps->top++;
}

void StackPop(ST* ps)
{
	assert(ps);
	assert(ps->top > 0);
	ps->top--;
}

STDataType StackTop(ST* ps)
{
	assert(ps);
	assert(ps->a);
	return ps->a[ps->top - 1];
}

int StackSize(ST* ps)
{
	assert(ps);
	return ps->top;
}

int StackEmpty(ST* ps)
{
	assert(ps);
	return ps->top == 0;
}